Significant Foreign Body Reaction Research Articles

Influence of Different Sling Materials on Connective Tissue Metabolism in Stress Urinary Incontinent Women

The aim of this study was to investigate the influence on the paraurethral connective tissue of different sling materials used in incontinence surgery. Biopsies from the paraurethral connective tissue were obtained intraoperatively from 16 women with stress urinary incontinence; all were operated on with the TVT procedure, 6 with Mersilene as the sling material and 10 with Prolene. Biopsies from 4 continent women with uterine bleeding irregularities, matched for age and parity, served as controls. New biopsies were obtained from all women after 2 years. The biopsies were examined histologically and analyzed for collagen concentration and solubility. An obvious inflammatory reaction with a significant increase in collagen extractability by pepsin was identified in patients where Mersilene was used as the sling material. A minimal inflammatory reaction without a significant change in collagen solubility was found in the Prolene group. In the control group no inflammatory reaction was seen. Mersilene gave rise to a significant foreign-body reaction in the paraurethral connective tissue after surgery. Such a reaction was not found with Prolene.

Porous Hydroxyapatite Granules For Alloplastic Enhancement Of The Facial Region

Hydroxyapatite is a biocompatible alloplast with the same chemical composition as bone. It is readily incorporated into host bone, does not undergo appreciable resorption, does not incite a clinically significant foreign body reaction, and resists infection. This article describes forms of hydroxyapatite, procedures for use, and clinical examples.

Patch incorporation in diaphragmatic hernia

Biomaterial insertion often is required for closure of congenital diaphragmatic hernia (CDH). The optimal biomaterial remains uncertain. This study was designed to compare a commonly used patch (polytetrafluoroethylene) with a recently available fabric, fluorinated polyester. The aim of this study was to determine the clinical performance, histological tissue-polymer interaction, bacterial adhesion, and shrinkage rates of biomaterial inserted endoscopically into a CDH lamb model. Polytetrafluoro-ethylene (PTFE) and fluorinated polyester (FP) were randomised for laparoscopic patch insertion into 12 lambs. All lambs (age <4 weeks) underwent 3-port laparoscopy, surgical creation of diaphragmatic hernia, and sutured patch placement. Two PTFE and 2 FP lambs were killed at 1-, 3-, and 6-month intervals postoperatively. Postmortem examination histopathology, electron microscopy, and specific bacterial broth immersion (Escherichia coil, Staphylococcus aurens, and epidermidis) were performed. All 12 lambs completed the study with intact patches that were fully peritonised. One abdominal adhesion was noted in a FP lamb at 6 months. FP was comparatively easier to insert, manipulate, and suture endoscopically. Histopathology findings showed that PTFE patches created a strong peripheral foreign body reaction with dystrophic calcification, whereas FP was well incorporated with intrapatch fibroblastic activity and neovascularsation. No significant difference in resistance to bacterial adhesion of relevant organisms was noted between the materials. Graft shrinkage for FP was 7% in one direction only, evident by 3 months. Fluorinated polyester has advantages in this laparoscopic lamb model. It shows rapid and sustained incorporation with intrapatch neovascularisation when compared with polytetrafluoro-ethylene's significant foreign body reaction. It was preferred for its endoscopic handling and suturing properties. The laparoscopic techniques used may contribute to the general lack of adhesions, and insufficient data are available to comment on the comparative effect of the materials on adhesion formation. No difference was demonstrated in resistance to bacterial adherence in the harvested materials.

Excision of cervical cystic lymphangioma using injection of hydrocolloid dental impression material: A technical case report

A lymphangioma, arising in an adult patient, was completely removed after injection of hydrocolloid dental impression material. The postoperative course was uneventful, with no sign of foreign-body reaction. The agar impression material, which had excellent tractability during operation, may be used as a filling material, as long as preoperative examinations show that the tumor does not involve major vessels or nerves.

Titanium and Glass-Ionomer Cement as Ossicular Replacement Materials: Biocompatibility Results after Implantation in the Rabbit

The middle ear poses unique challenges when finding suitable materials for ossicular reconstruction, primarily because of its link to the external environment via the eustachian tube, which leads to a greater potential for exposure to infectious agents. In this animal study, the biocompatibilities of titanium and glass-ionomer cement were assessed in the middle ear of the rabbit after being implanted as total ossicular replacement prostheses (TORPs) or as free pins. Animals were sacrified after 28, 84, 168, 336, or 504 days or 2 years, and a cutting saw technique was used to prepare slides for light microscopy. Slides were examined for mucosal coverage and any sign of foreign body reaction. Both materials showed good acceptance in the middle ear. After 28 days, the TORPs were covered by middle ear mucosa. As expected, it took a longer time (up to 504 days) to cover the free implants. An interesting finding was the growth of new bone on both the surface of the titanium implants and the glass-ionomer prostheses. The results of this animal study indicate that both titanium and glass-ionomer cement are favorable materials for ossicular replacement prostheses.

Titanium as a biomaterial for ossicular replacement: results after implantation in the middle ear of the rabbit.

The middle ear poses unique challenges when finding suitable materials for ossicular reconstruction, primarily because of its link to the external environment via the eustachian tube and, hence, its greater exposure to infectious agents. In this study, the biocompatability of titanium was examined in the middle ear of rabbits by using light and scanning electron microscopy. Implants were placed as middle ear prostheses or as free implants. These were inspected at 28 days, 84 days, 168 days, 336 days and 504 days following implantation for mucosal coverage, percent epithelization and any sign of foreign-body reaction. After 28 days, the prostheses were covered by regular mucosa. Although a majority of the free implants took up to 336 days for complete epithelialization, some of the free implants were not epithelialized even at day 504. There were no inflammatory cells observed on the surface of the material, nor were unusual amounts of fibrous tissue seen. In addition, the titanium material exhibited an affinity toward bone. The results of this animal experiment indicate that titanium is a favorable material for ossicular replacement prostheses.

Postoperative Cellular Reaction on Various Intraocular Lens Materials

The presence of cellular deposits on the surface of intraocular lenses (IOLs) is a manifestation of: (1) the breakdown of the blood-aqueous barrier produced by surgery; and (2) foreign body reaction induced by lens implantation. The purpose of this study was to assess the presence of cellular deposits on the surfaces of various IOL materials. Fifty patients scheduled for cataract surgery were randomized into five groups of ten patients each and received IOLs of the following materials: conventional polymethylmethacrylate (PMMA), surface-passivated PMMA, heparin-surface modified PMMA, poly-hydroxyethylmethacrylate (HEMA) hydrogel and silicone. Patients were examined at 7 days, 30 days, 90 days, and 180 days after surgery. All eyes were observed first via slit-lamp and then using a contact specular microscope for photographic documentation. Small, spindle-shaped cells were observed on all IOLs in the early postoperative period. Epithelioid cells appeared approximately 30 days after surgery on all PMMA IOLs, but most particularly on conventional PMMA IOLs. No cells were observed on poly-HEMA and silicone IOLs. The decreased number of epithelioid cells discovered in the early postoperative period may indicate a reduction in the inflammatory process induced by surgery. The permanence of epithelioid cells on IOL surfaces may be a sign of foreign body reaction. The results of this study indicated that poly-HEMA and silicone IOLs showed fewer cellular deposits than PMMA IOLs, suggesting that they may be better tolerated than PMMA IOLs.

Use of mother of pearl as a bone substitute - Experimental study in sheep

The authors present the first results of an experimental study using mother of pearl implants which were placed in the femur of sheeps. The aim of this study is to explore the possible applications of this new biomaterial for bone substitution in orthopaedic surgery. Radiologically it seems that there is extremely good acceptance of the implants in the host bone without mobilization, resorption or lysis of the peripheral bone and in all cases neotrabeculae in contact and in the neighbourhood of the implants. Histologically in the course of 3 months no sign of foreign body reaction were observed and the implants were not subject to biodegradation. By light microscopy osteogenic activity was detected within an osteoprogenitor cellular layer lining the implant resulting in a complete sequence of new bone formation. Nacre appeared to bind directly to new formed bone without intervening fibrous tissue. These preliminary results are extremely encouraging and they should be confirmed by the complete analysis of the sections corresponding to the longest follow-up. These results, combined with mechanical qualities of the mother of pearl implants allows us to hope that there are possible applications in orthopaedic surgery (blocks for intervertebral arthrodesis or for reconstruction in arthroplasty revisions, osteotomy wedges, butresses in recurrent shoulder and dislocation, screws for specific indications).

FOREIGN-BODY REACTION AND THE COURSE OF OSTEOLYSIS AFTER POLYGLYCOLIDE IMPLANTS FOR FRACTURE FIXATION

Foreign-body reaction to polyglycolide (PGA) implants has been described in man. Many animal experiments have verified the mechanical properties of fixation devices made from PGA, but a significant foreign-body reaction has not been described. We studied the effect of PGA rods in 12 sheep with standardised osteochondral fractures of the medial femoral condyle fixed with uncoloured, self-reinforced PGA rods (Biofix). Radiographs were taken at intervals ranging from two weeks to two years, and the sheep were killed at intervals ranging from six to 24 months. All knees were examined histologically. Eleven of the 12 fractures healed radiologically and histologically. Moderate to severe osteolysis was seen at four to six weeks with maximum changes at 12 weeks in ten animals. Six knees showed fistula-like connections between the implant site and the joint space. Three developed synovitis, one with inflammatory changes involving the whole cartilage and one with destruction of the medial condyle. Although in our study osteochondral fractures fixed with PGA rods healed reliably, there were frequent, significant foreign-body reactions. Caution is needed when considering the use of PGA fixation devices in vulnerable regions such as the knee.

Polymeric stenting in the porcine coronary artery model: Differential outcome of exogenous fibrin sleeves versus polyurethane-coated stents

Objectives. In a porcine coronary model, fibrin film soaked for 3 h in heparin was used as a circumferential coating on a tantalum stent to assess the effect of this naturally occurring biopolymer on arterial healing. The results were compared with those obtained with medical grade polyurethane-coated stainless steel stents.Background. Thrombus plays an important role in healing after arterial injury and may affect the development of neointimal hyperplasia. Manipulation of the initial thrombus may alter the healing response. To study this, we placed a template of fibrin in a porcine coronary artery restenosis model.Methods. Thirty-four fibrin film stents were delivered in 20 swine. Oversizing was avoided, to prevent deep arterial injury, by placement of optimally sized stents. Initial patency of the syented vessel was confirmed by angiography.Results. Three fibrin-stented swine died within 48 h; in each, the stent was occluded with a fibrin/red blood cell mass. In two of these three, a portion of the exogenous fibrin had become detached from the stent and partially occluded the lumen. Of the remaining 31 stents, all were patent at elective sacrifice at 28 days. Eightyfour percent had a diameter stenosis <50%, and the mean (± SD) diameter stenosis was 32.3 ± 13%. There was no evidence of significant foreign-body giant-cell reaction. These results contrasted with the medical grade polyurethane-coated stents placed according to the same protocol without oversizing. Twelve of these stents were placed; six swine died of thrombotic occlusion within the 1st 48 h. At elective sacrifice at 28 days, the remaining polyurethane-coated stents were occluded by marked neointimal hyperplasia.Conclusions. Fibrin film-coated stents seem promising as a template for modifying the local response to arterial injury and for potentially decreasing restenosis rates.

Production of purified alginates suitable for use in immunoisolated transplantation

Alginate is used as a matrix for immunoisolation of cells and tissues in vivo. We have demonstrated previously that commercial alginates contain various fractions of mitogenic impurities and that they can be removed by free flow electrophoresis. The use of purified material is a necessity in order to reveal the parameters that control biocompatibility of the implanted material (such as stability, size, surface charge and curvature, etc.). In this study, we present a protocol for the chemical purification of alginates on a large-scale. Beads made from alginates purified by this multi-step chemical extraction procedure did not induce a significant foreign body reaction when implanted for 3 weeks either intraperitoneally or beneath the kidney capsule of Lewis or non-diabetic BB/Gi rats.

注入用コラーゲンの組織内反応

Injectable collagen has been conventionally used for vocal fold augmentation in human subjects. One inherent problem with this treatment, however, has lied in the persistence of the implants.To explore this problem, injectable collagen, 3% atelocollagen extracted from a calf, was injected into both the lamina propria and muscle layers in canine vocal folds. A histologic study was performed one year postoperatively.We were unable to detect evidence of significant foreign body reaction and migration during the follow-up period. However, two patterns of reaction were seen : 1. cellular infiltration, 2. colonization by host fibroblasts and nourishing capillaries.In immunohistochemical study it was revealed that when the implanted collagen was colonized by host cells, the immunologic features of the implant were preserved.

Hypospadias Repair Usingl Laser Welding of Ventral Skin Flap in Rabbits: Comparison with Sutured Repair

We tested the feasibility of laser welding in hypospadias repair. A total of 30 New Zealand white rabbits (2 groups of 15) underwent creation of distal hypospadias. In the control group ventrally placed skin flaps were created and sutured to the urethra. In the experimental group the ventrally placed skin flaps were welded to the urethra using a continuous wave diode laser (808 plus or minus 1nm., 6.25 watts per cm.2). The welded anastomoses were strengthened by applying a solder of fibrinogen combined with a laser energy-absorbing dye. No stents were left indwelling. Operative time using laser welding was considerably less than that with sutured repair. No fistulas were seen in the welded urethras, and no significant foreign body reaction was identified in the laser welded repairs.Hypospadias repair in the rabbit using the laser welding technique seems to be a feasible alternative to suture repair. Topical energy-absorbing dyes that enhance thermosetting solders further increase weld strength while reducing collateral thermal damage to target tissues.

Release of peptides from sustained delivery systems (microcapsules and microparticles) in vivo

Sustained delivery systems (microcapsules, microparticles, or implants) developed for once a month administration of peptides are efficacious and convenient. Long acting formulations of several bioactive peptides are based on microcapasules of a biodegradable polymer poly(DL-lactide-co-glycolide) (PLG), but a better understanding is required of the mechanism of the peptide release from the microcapsules, which is assumed to be primarily by diffusion through pores. In order to clarify this mechanism, microcapsules and microparticles of the agonist [D-Trp6]-LHRH and microcapsules of the LHRH antagonist SB-75 were given i.m. to rats 2 h and 1, 2, 4, 7, 14 and 21 days before histological and immunohistochemical investigation. Signs of biodegradation of the PLG matrix could be seen the first day after the injection, in a form of vacuole development in the interior of the particles and connected with the presence of macrophages within the matrix. The microcapsules showed excellent tissue-compatibility, and no significant foreign body reaction was detected. Immunohistochemical study on the microcapsules revealed no visible decrease in peptide concentration in the remnants of the matrix even 2 weeks after the injection. Evaluation of serum [D-Trp6]-LHRH showed that after an initial burst, both microcapsules and microparticles maintained elevated serum [D-Trp6]-LHRH levels for more than 3 weeks. Our results suggest that the previously proposed mechanisms do not reflect the experimental findings, particularly for the insoluble peptides. The peptide release from the PLG microcapsules or microparticles appears to be controlled mostly by the speed of the biodegradation of the polymer matrix and the diffusion of the peptides from the PGL is negligible.

Is n-butyl-2-cyanoacrylate a biocompatible coating material for biodegradable fracture fixation devices? An experimental study on rats

The effect of n-butyl-2-cyanoacrylate monomer and polymer on the repair characteristics of cancellous bone was evaluated in an experimental study in which 105 male Wistar rats were operated on. A transverse drill channel 2mm in diameter and 5mm long in the femoral condyle was filled with a cylindrical implant of n-butyl-2-cyanoacrylate polymer or liquid n-butyl-2-cyanoacrylate monomer, which was polymerized in the tissue. The drill channel was left empty in the control group. Follow-up periods were one, three, six, 12, 24, 36 and 48 weeks. Radiographic, histologic, histomorphometric, oxytetracycline fluorescence and microradiographic studies were done. N-butyl-2-cyanoacrylate polymerdid not delaybone healing and was well tolerated by rat's cancellous bone tissue without signs of foreign body reaction or prolonged inflammation reaction. The polymerization of n-butyl-2-cyanoacrylate monomer caused the development of a narrow zone of bone necrosis or connective tissue around the implant depending on whether or not blood had interfered in the polymerization reaction. Bone necrosis and connective tissue worked as a biological and mechanical obstruction for bone healing towards the implant although there was no disturbance in the regenerative process in the trabecular network surrounding the implant.

Injectable collagen in laryngeal rehabilitation

Glottic insufficiency has been successfully managed by Teflon augmentation of paretic vocal cords over the past two decades. Collagen fulfills the criteria for a suitable bioimplant and is an attractive alternative as it is a normal constituent of the extracellular protein matrix. This study explores the use of modified bovine collagen injected into the canine larynx. Clinical situations are simulated by creating lesions and injecting collagen at different sites. The technique permits precise placement and quantification. Histologic study of the collagen implant fails to show evidence of significant foreign body reaction. The injected collagen appears similar to viable connective tissue and is colonized by host fibroblasts and nourishing capillaries.

Electron-microscopic investigation of tattoos in rabbit skin.

Electron-microscopic evidence of morphological signs of foreign body reactions can be seen in the first 27 days after tattooing. The chemical additives of china ink are eliminated in the acute leukocyte phase and the following histiocytic-macrophagic phase. The macrophagic cells move together and gradually confluence to form giant cells within 14 days.

Subclinical reduction in airflows after Teflon injection of vocal cord.

Results of intracordal Teflon injection for symptoms of unilateral vocal cord paralysis have been excellent. There seems to be no significant long-term foreign body reaction or limitation to maximum airflows. However, acute inflammatory reactions and airflow obstruction have been reported. The objective of the present study was to evaluate the frequency, extent, and duration of airway obstruction following Teflon injection. Forced inspiratory and expiratory airflows were measured in seven consecutive patients before, 24 hours, and 10 days after Teflon injection. Significant variable upper airway obstruction, as demonstrated by an increase in the ratio of forced expiratory airflows at 50% Vital Capacity to the forced inspiratory airflows at the same lung volume (VE50/VI50), was found in each subject. At 24 hours after the injection this ratio increased from a baseline of .098 +/- 0.50 (mean +/- S.D.) to 1.41 +/- 0.67 (P less than 0.01), and returned to baseline values in 10 days (0.95 +/- 0.14). We conclude that Teflon injection into a paralyzed vocal cord creates a significant inspiratory airway obstruction that is reversible in 10 days.

Chronic vascular reactions to steel coil occlusion devices.

Original Gianturco steel coil vascular embolization devices and two modifications were compared for their occlusive effects and for the degree of adverse reaction in the surrounding vessel wall. Modifications consisted of silk or Ivalon replacing the wool strands of the original device. Single coils were placed into the left renal artery of nine mixed breed swine and restudied 3 months later. The bare coils did not occlude the vessels nor lead to significant foreign body reaction. Wool, silk, and Ivalon coils produced prompt and sustained renal artery occlusion. Upon histologic examination of the vessel wall, foreign body and chronic inflammatory reaction was found to be strongest against wool. This reaction was less with silk and markedly diminished with Ivalon. The results indicate that silk and Ivalon coils, while having the same occlusive effect, are preferable to wool coils if less local reaction is desired.

Complications of silicone implant surgery in the metacarpophalangeal joint

Of 162 metacarpophalangeal silicone prostheses inserted from 1967 to 1973, fifteen fractured, two were associated with an infection, and there was one case of skin necrosis. A recurrence of ulnar drift occurred in four hands. Three prostheses had to be removed and in one such case additional significant foreign-body reaction was evident. Although the complication rate was over 10 per cent, the failure rate was fairly low.